lipo 1500mah 1300mah 45c c-rating 75c

So in my early days of drone flying I wanted to go budget and ordered two 1500mah 45c 4s lipos from Floureon for 29$. I have been using them along with my tattu 1500mah 75c 4s lipos and I don't notice a difference. Same flight time same punch power. Am I just over working my 45c batteries...